The present invention relates to a clutch-brake device for a mechanical press. More specifically, the present invention relates to a clutch-brake device that is constructed so that the pushing force of a piston member of a fluid pressure cylinder is directly delivered to a clutch plate which rotates as a unit with a case member.
A conventional clutch-brake device of a mechanical press has a driving force delivery system, wherein the driving force inputted to the fly wheel is delivered to the crank shaft. The clutch-brake device is fundamentally constructed from the following: a stationary member, rotationally supports a fly wheel; a rotation shaft, rotationally supported by the stationary member; a case member, affixed to the fly wheel; a rotation input member, affixed to the rotation shaft; a multiple disk clutch, between the case member and the rotation input member; a multiple disk brake, between the stationary member and the rotation input member; a fluid pressure cylinder, rigidly provided on the case member switching the multi-disk clutch and the multi-disk brake.
With this type of clutch-brake device, when the multi-disk clutch is switched to the connected state by the fluid pressure cylinder, the multi-disk brake is switched to a disconnected state. In this state, the driving force inputted to the fly wheel is delivered to the crank shaft via the case member, the multi-disk clutch, the rotation input member, the rotation shaft, and the like. When the multi-disk clutch is switched to the disconnected state, the multi-disk brake is switched to the connected state, and the rotation shaft which is rotating is braked.
In order to couple the switchings of the multi-disk clutch and the multi-disk brake, the clutch-brake device of the mechanical press of Japanese Laid-Open Patent Publication Number 7-51898 has a hub, acting as a rotation input member, rigidly fitted outside the rotation shaft. On both ends in the axial direction, the hub is provided with a clutch push plate, which is opposite the multi-disk clutch, and a brake push plate, which is opposite the multi-disk brake. The clutch push plate and the brake push plate are both joined to the hub by a spline, thereby rotating as a unit with the hub. The clutch push plate and brake push plate are linked by a plurality of bolts which pass through the hub, thereby moving as a unit in the axial direction.
When the fluid pressure cylinder is driven, the multi-disk clutch is pushed by the piston member via the clutch push plate and switched to the connected state. Then, the brake push plate is moved in the direction separating from the multi-disk brake. The multi-disk brake is no longer being pushed by the brake push plate, and it is switched to a disconnected state. When the fluid pressure of the fluid pressure cylinder is released, the multi-disk brake, via the brake push plate, is switched to the connected state by a plurality of brake springs, which are housed inside the hub. Then, the clutch push plate moves as a unit with the piston member in the direction separating from the multi-disk clutch. The multi-disk clutch is no longer being pushed by the clutch push plate, and it is switched to the disconnected state.
However, with the conventional clutch-brake device for a mechanical press of Japanese Laid Open Patent Number 7-51898, the piston member of the fluid pressure cylinder rotates as a unit with the fly wheel, and the clutch push plate rotates as a unit with the rotation shaft. As a result, when switching the multi-disk clutch between the connected and disconnected states, there is slipping caused by the difference in rotation speeds between the piston member and the clutch push plate, resulting in abrasion of the piston member and the clutch push plate, thereby reducing durability.
With the above clutch-brake device, the clutch push plate is provided between the multi-disk clutch and the piston member. By pushing this clutch push plate, the multi-disk clutch is connected. As a result, when there is abrasion in the clutch push plate or piston member, the efficiency of delivery of the pushing pressure of the piston member to the multi-disk clutch is reduced. In addition, the device becomes larger in the axial direction by the amount of the thickness of the clutch push plate, and manufacturing costs increase. When the multi-disk clutch is disconnected, the movement of the piston member of the fluid pressure cylinder is not restricted. As a result, there is looseness in the piston member.
It is an object of the present invention to provide a clutch-brake device for a mechanical press which overcomes the foregoing problems.
More specifically, it is an object of the present invention is to provide a clutch-brake device for a mechanical press, wherein abrasion of the piston member and the like is prevented, durability is heightened, manufacturing costs are reduced, and looseness of the piston member is prevented.
The present invention is a clutch-brake device, provided on a driving force delivery system delivering driving force, which is inputted to a fly wheel of a mechanical press, to a crank shaft, comprising a stationary member, rotationally supports the fly wheel; a rotation shaft, having at least one part rotationally supported by the stationary member and transferring the driving force to the crank shaft; a multi-disk clutch, provided between a case member affixed to the fly wheel and a rotation input part of the rotation shaft; a multi-disk brake, provided between the stationary member and the rotation input part of the rotation shaft; a fluid pressure cylinder, rotating as a unit with the fly wheel and switching the multi-disk clutch and the multi-disk brake; and an output part, on the piston member of the fluid pressure. cylinder and delivering the pushing force of the piston member to a clutch plate which rotates as a unit with the case member.
The pushing force of the piston member of the fluid pressure cylinder is delivered to the clutch plate via the output part, switching the multi-disk clutch to the connected state. In this connected state, the driving force inputted to the fly wheel is delivered to the crank shaft via the case member, the multi-disk clutch, the rotation input part, and the rotation shaft. Coupled with the switching of the multi-disk clutch to the connected state, the multi-disk brake switches to the disconnected state. Coupled with the switching of the clutch plate to the disconnected state, the multi-disk brake is switched to the connected state, and the rotation shaft is braked.
In this clutch-brake device, the piston member of the fluid pressure cylinder rotates as a unit with the fly wheel and case member. The clutch plate rotates as a unit with the case member and fly wheel. As a result, when directly pushing the clutch plate with the output part of the piston member, a rotation speed difference does not arise between the output part and the clutch plate. There is no abrasion of the piston member or clutch plate, and the durability of the multi-disk clutch and piston member is dramatically improved. In addition, because the pushing force of the piston member is directly delivered to the multi-disk clutch, the multi-disk clutch can be made smaller in the axial direction, thereby reducing manufacturing costs.
According to a preferred embodiment of the present invention, the clutch-brake device also has the following: an annular member, opposite the piston member of the fluid pressure cylinder with a small gap therebetween, rotatably movable in an axial direction and rotating as a unit with the rotation shaft; a brake-side annular member, near and opposite the multi-disk brake; a plurality of bolts, connecting the brake-side annular member to the annular member; and a thrust bearing, between the piston member and the annular member.
When switching the multi-disk clutch to the connected state, the annular member is pushed and moved by the piston member of the fluid pressure cylinder via the thrust bearing. Due to this annular member, the brake-side annular member, via a plurality of bolts, moves toward the disconnect side, and the multi-disk brake switches to the disconnected state. In other words, even if there is a rotation speed difference between the annular member, which rotates as a unit with the rotation shaft, and the piston member, which rotates as a unit with the fly wheel, this rotation speed difference is absorbed by the thrust bearing. As a result, abrasion of the annular member and the piston member is prevented, and durability is heightened.
It is preferable to have a plurality of brake springs, which elastically impel the brake-side annular member and the annular member toward the piston member, bringing the multi-disk brake to the braking state (connected state). In this situation, when the fluid pressure of the fluid pressure cylinder is released, due to the elastic impelling force of the plurality of brake springs, the multi-disk brake is pushed by the brake-side annular member and is switched to the braking state. In addition, the output part of the piston member is moved in a direction away from the clutch plate via the brake side annular member, plurality of bolts, and annular member, and the multi-disk clutch is switched to the disconnected state.
It is preferable to have the above brake-side annular member be near and opposite the brake disk, which rotates as a unit with the rotation input part of the rotation shaft. When switching the multi-disk brake to the braking state, the brake-side annular member contacts the brake disk, but because the brake-side annular member and the brake disk both rotate as a unit with the rotation shaft, there is no slippage resulting from rotation speed differences between the brake-side annular member and the brake disk. As a result, their abrasion is prevented, and durability is heightened.
It is preferable to provide a compression spring, which elastically impels the above piston member toward the annular member. The elastic impelling force of the compression spring assures that the piston member is always pushed against the thrust bearing. As a result, looseness in the thrust bearing or piston member is prevented. Furthermore, the elastic impelling force by the compression spring is set to be smaller than the elastic impelling force of the plurality of brake springs.
The above driving force delivery system has a gear member, affixed to the rotation shaft, which engages with a gear affixed to the crank shaft. It preferably is provided with a support part, which rotationally supports, via a bearing, a part of the rotation shaft that is on the opposite side as the stationary member with respect to the gear member. The rotation shaft can be supported on both sides of the gear member by the stationary member side and this support part. As a result, sagging of the rotation shaft is suppressed, and a smooth engagement of the gear member and the gear on the crank shaft side is maintained.
The above driving force delivery system has a gear member, affixed to the rotation shaft, which engages with a gear affixed the crank shaft. The support part, which rotationally supports, via a bearing, a part of the rotation shaft on the stationary member side with respect to the gear member. In this situation, on the rotation shaft, a large space near the gear on the crank shaft side is maintained. As a result, this is advantageous in terms of machinery layout.
The above rotation input part can be constructed as a rotation input member which is joined by a spline to the rotation shaft so that movement in the axial direction is not possible. In this situation, the parts of the rotation shaft, other than the rotation input part, can be made smaller, and the manufacturing costs for the rotation shaft is reduced further.
Furthermore, when placing the above plurality of bolts so that they pass through the rotation input part, the space for placing these plurality of bolts can be made smaller. and the size of the clutch-brake device is reduced further.
Preferably, an oil housing part, which houses oil for the multi-disk clutch and multi-disk brake, is provided in the area surrounded by the stationary member, the fly wheel, the case member, and the piston member of the fluid pressure cylinder. Preferably, a plurality of oil passages, for oil circulation and which is in the radial direction, are formed at certain intervals in the circumferential direction on the ring-shaped output part of the piston member.
The multi-disk clutch and the multi-disk brake can be cooled by the oil inside the oil housing part. The other sliding parts can be lubricated by the oil. Furthermore, the circulation of oil can be facilitated by the plurality of oil passages in the output part.
When a plurality of spring housing parts, housing the plurality of brake springs, is formed in the interior of the above rotation input part, this is advantageous in terms of the space for arranging the plurality of brake springs. The clutch-brake device can be made smaller.
When having a compression spring between the head-side case member and the piston member of the fluid pressure cylinder, the piston member is reliably impelled elastically in the direction of the annular member by this compression spring. Because the compression spring is built into the inside of the fluid pressure cylinder, the clutch-brake device is therefore made smaller.
The above, and other objects, features, and advantages of the present invention will become apparent from the following description read in conjunction with the accompanying drawings, in which like reference numerals designate the same elements.